The assignee of this invention has manufactured and sold commercially toner cartridges of two different general designs. For its larger laser printers the cartridge has contained a pump to meter toner of the kind disclosed in U.S. Pat. Nos. 5,012,289 to Aldrich et al. and 5,101,237 to Molloy, while the external structure of the cartridge is as disclosed in U.S. Pat. No. 5,136,333 to Craft et al. Details of other elements in the cartridge have varied.
For a smaller, light emitting diode printer, the cartridge is as disclosed in U.S. Pat. No. 5,337,032 to Baker et al., which has a toner hopper extending well below a level having the toner adder roller and which has independent driven systems for the photoconductor roller and for the developer roller system as disclosed in U.S. Pat. No. 5,331,378 to Baker et al.
This cartridge has a hopper exit above a vertical barrier. The outside of the barrier is a declining surface. Such a configuration is believed to be generally conventional. This invention employs an agitator operative at the exit surface, which is not believed to be in the prior art.